One step connector

ABSTRACT

This invention relates to a one step coaxial connector for an annular corrugated coaxial cable. The components of the connector include an outer conductor clamping back nut, a collet and a body. The collet ( 1 ) enhances electrical performance by providing a full 360 degree contact with the outer conductor. In addition, an O-ring is used to provide a seal between the back nut and outer conductor of the cable. When the back nut ( 2 ) is screwed into the body ( 5 ), the collet ( 1 ) is forced further into the interior portion ( 11 ) of the connector body ( 5 ). The resilient fingers of the ( 1 ) collet are forced to close radially around the first corrugation groove ( 3 ) of the cable&#39;s outer conductor. In addition, an O ring ( 4 ), that initially resides in a cavity ( 12 ) created by the collet ( 1 ) and the back nut ( 2 ), is forced into a corrugation groove of the cable&#39;s outer conductor. A bore ( 6 ) on the back nut ( 2 ) provides the proper diameter to compress the O-ring ( 4 ) to provide a tight seal.

FIELD OF INVENTION

This invention is related to the field of connectors. More particularly,this invention relates to a coaxial connector for an annular corrugatedcoaxial cable which can be installed in the field without special tools.

BACKGROUND OF INVENTION

Currently existing one piece connectors present certain problems. U.S.Pat. No. 6,809,964 discloses a connector which uses ball bearings thatengage a corrugation groove of the cable's outer conductor. However, theball bearings do not make a 360 degree contact. Therefore, passiveintermodulation (PIM) performance can be degraded. Also, although ituses an O-ring, the O-ring doesn't engage the corrugation groove.Instead it seals on the crest of a corrugation, that can be subjected todamage when the jacket is removed. Lastly, a special tool is required totrim the cable before the connector can be installed.

Another connector made by Spinner must be installed in a multistepoperation. First, the O-ring must be installed. Next, the connector isplaced over the corrugated shield and O-ring of the corrugated cable. Inaddition, the O-ring must be compressed by hand pressure as theconnector is installed. This limits the amount of squeeze the O-ring canbe compressed. Finally, the Spinner connector uses a non-standard toolcalled a spanner wrench for large size connectors.

SUMMARY OF THE INVENTION

The present invention is a one step connector, comprising a body, havinga first end with a threaded interior portion which mates with a back nuthaving a threaded exterior portion. In addition, it comprises a collethaving resilient fingers and an oversized O-ring. The body furthercomprises a taper between its base and side for closing the resilientfingers radially by pressing on an end of the resilient fingers. Locatedmidway on the resilient fingers is a ramp which makes contact with aninterior surface of the back nut to also aid in closing the resilientfingers. Furthermore, the back nut comprises a bore which compresses theO-ring when the connector is being clamped to a cable. In addition, theback nut includes a shoulder to provide rigidity to the collet byengaging a tab of the collet.

In another preferred embodiment, the present invention is a coaxialcable assembly comprising the one step connector and a RF coaxial cablehaving an annular corrugated outer conductor, a center conductor and adielectric material located between the outer conductor and the centerconductor.

In still another preferred embodiment, the present invention is a methodof sealing a connector to a cable. When a backnut is screwed into abody, a collet is collapsed around a first corrugation groove of acable's jacket. In addition, a lubricated O-ring is pushed by resilientfingers of the collet out of a cavity into a corrugation groove in thecable's outer conductor. Furthermore, the O-ring is compressed by a borelocated on the backnut.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of the one step connector in the “as supplied”condition ready to be clamped onto the coaxial cable.

FIG. 2 is a view of the one step connector after being installed on thecoaxial cable, i.e., the installed condition.

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to a coaxial connector for an annular corrugatedcoaxial cable. In addition, it relates to a method for attaching aconnector to the outer conductor of an annular corrugated coaxial cablewithout installing extra parts. Therefore, extra parts such as O-ringsdo not have to be added later in an additional step to seal theconnector/cable interface connection from the environment. In addition,the connector can be installed in the normal manner in the field andwithout using special trim tools by taking the connector apart.Furthermore, the connector has no loose parts.

Connectors for radio frequency cables having annular corrugated outerconductors generally require a means to firmly grasp or secure theconnector to the outer conductor of the cable. The RF cable has aannular corrugated outer conductor, a center conductor, and a dielectricfoam between both conductors. The components of the one step connectorinclude an outer conductor clamping back nut, a collet and a body. Thecollet (1) enhances electrical performance by providing a full 360degree contact with the outer conductor (3). In addition, an O-ring isused to provide a seal between the back nut and outer conductor of thecable. The O-ring (4) provides an environmental seal by keeping moistureout.

The one step connector consists of three pieces—the collet (1), the backnut (2) and the body (5). The connector is assembled by screwing theback nut (2) and the body (5) together. The body (5) of the connectorhas an interior threaded portion at a first end having a thread depthand pitch to allow coupling with a threaded exterior portion of the backnut (2). The backnut (2) and body (5) have standard wrench flats fortightening the connector to the cable in the field.

A collet (1) having resilient fingers (13) sits in the interior portion(11) of the connector body (5). Its resilient fingers (13) extend intoan interior surface of the back nut (2). FIG. 1 shows the collet (1) inthe forward expanded position relative to the back nut (2). Thisposition allows the collet to engage the cable's outer conductor (3)corrugations. The interior portion (11) of the connector body (5) alsocontains a taper (8) between the base and side of the connector body(5). The taper (8) is in contact with one end of the fingers (13) of thecollet (1). The collet (1) also has a ramp (7) integrally formed intothe midway of the fingers (13) which makes contact with the interiorsurface of the back nut.

When the backnut (2) is mated with (or screwed into) the body (5), thecollet (1) is forced further into the interior portion (11) of theconnector body (5). See FIG. 2. Since the collet can not enter the backnut (2) in the expanded condition, the resilient fingers (13) of the (1)collet are forced to close (or collapse). Both the taper (8) of theconnector in contact with one end of the fingers (13) and the ramp (7)located about midway on the fingers (13) in contact with the interiorsurface of the back nut (2) provide an inward radial force to force theresilient fingers (13) of the (1) collet to collapse (or close)radially. As a result, the formed ends of the independent resilientfingers (13) of the collet (1) close radially around the firstcorrugation groove of the outer conductor (3). (In effect, the colletfunctions like a spring-like lock washer and holds the connector to thecable.)

Furthermore, the collet comprises a tab (9) which engages a shoulder(10) of the back nut (2) just before the collet is fully inside the backnut (2). The shoulder provides the necessary rigidity to the collet inthe clamped position by effectively reducing the overall length tothickness ratio of the resilient fingers (13) by about a 2:1 ratio.

In addition, an O ring (4), that initially resides in a cavity (12)created by the collet (1) and the back nut (2), is forced into acorrugation groove of the cable's outer conductor (3). (In a preferredembodiment, the resilient fingers (13) of the collet (1) are rigidenough to push the O-ring (4) out of the cavity). A bore (6) on the backnut (2) provides the proper diameter to compress the O-ring (4) toprovide a tight seal. In a preferred embodiment, the connector uses anoversized O-ring that can be highly compressed as the connector isclamped to the cable. The O-ring has a high degree of compression sothat the one step connector can fit over cables with normal tolerancevariations. The O-ring can be compressed up to about half of the crosssection in this embodiment. In summary, when the unit is screwedtogether, the O-ring (4) moves into a groove of the outer conductor andthe collet (1) moves into the end groove of the outer conductor (3).

In a preferred embodiment, the front portion, or free end, of theresilient fingers (13) are bent outward to provide a cutting guide totrim the cable in the event the installer does not have the proper trimtool. In addition, the outward bend allows the fingers (13) to makecontact with the body (5) of the connector to provide rigidity to thefingers (13) in the clamped position.

While the invention has been disclosed in this patent application byreference to the details of preferred embodiments of the invention, itis to be understood that the disclosure is intended in an illustrativerather than in a limiting sense, as it is contemplated that modificationwill readily occur to those skilled in the art, within the spirit of theinvention and the scope of the appended claims and their equivalents.

What is claimed is:
 1. A one step connector, comprising: a body; abacknut threadably attached to said body; a collet seated in said bodyhaving resilient fingers which close radially; and an O-ring, whereinsaid O-ring initially resides in a cavity located between said colletand said backnut, whereby said resilient fingers push said O-ring fromsaid cavity when said backnut is threadably attached to said body. 2.The connector according to claim 1, wherein said body comprises a firstend with a threaded interior portion; and said back nut comprises athreaded exterior portion.
 3. The connector according to claim 1,wherein said body further comprises a taper between a base and a side ofsaid body, whereby said taper on said body closes said resilient fingersradially by pressing on an end of said resilient fingers.
 4. Theconnector according to claim 1, wherein said collet further comprises aramp located about midway of said resilient fingers, whereby said rampmakes contact with an interior surface of said back nut and closes saidresilient fingers.
 5. The connector according to claim 1, wherein saidcollet further comprises a tab and said back nut further comprises ashoulder, whereby said shoulder provides rigidity to said collet byengaging said tab of said collet.
 6. The connector according to claim 1,wherein said O-ring is lubricated and oversized, whereby said O-ringpasses freely over a cable, whereby said resilient fingers push saidO-ring from said cavity to a corrugation groove in a cable's outerconductor when said backnut is threadably attached to said body.
 7. Theconnector according to claim 1, wherein said back nut further comprisesa bore, whereby said bore compresses said O-ring when said connector isclamped to a cable.
 8. The connector according to claim 3, wherein saidcollet further comprises a ramp located about midway of said resilientfingers and a tab; wherein said body comprises a first end with athreaded interior portion; wherein said O-ring is oversized; whereinsaid resilient fingers push said O-ring from said cavity to acorrugation groove in a cable's outer conductor when said backnut isthreadably attached to said body; and wherein said back nut comprises athreaded exterior portion, an interior surface, a shoulder and a bore,whereby said ramp makes contact with an interior surface of said backnut and closes said resilient fingers, said shoulder provides rigidityto said collet by engaging said tab of said collet, and said borecompresses said O-ring when said connector is clamped to a cable.
 9. Theconnector according to claim 1, wherein said connector is radiofrequency coaxial cable connector.
 10. A method of sealing a connectorto a cable, comprising the steps of: mating a backnut with a body;closing a collet around a first corrugation groove of a cable's outerconductor; and pushing an O-ring from a cavity located between saidcollet and said backnut to a corrugation groove in said cable's outerconductor.
 11. The method according to claim 10, wherein resilientfingers of said collet push said O-ring from said cavity.
 12. The methodaccording to claim 10, wherein said step of closing said colletcomprises closing resilient fingers of said collet radially.
 13. Themethod according to claim 10, further comprising the step of providingrigidity to said collet.
 14. The method according to claim 10, furthercomprising the step of compressing said O-ring after it is pushed fromsaid cavity.
 15. The method according to claim 12, wherein a taper onsaid body collapses resilient fingers of said collet radially bypressing on at least one end of said resilient fingers.
 16. The methodaccording to claim 12, wherein a ramp on resilient fingers of saidcollet in contact with an interior surface of said backnut collapsessaid resilient fingers radially.
 17. The method according to claim 12,further comprising a tab of said collet engaging a shoulder of saidbacknut, whereby a length to thickness ratio of said resilient fingersis reduced.
 18. The method according to claim 13, wherein said rigidityis provided to said collet by a shoulder of said backnut engaging a tabof said collet.
 19. The method according to claim 14, wherein saidO-ring is compressed by a bore on said back nut.
 20. The methodaccording to claim 11, further comprising the steps of: closingresilient fingers of said collet radially; providing rigidity to saidcollet by a shoulder of said backnut engaging a tab of said collet; andcompressing said O-ring after it is pushed from said cavity.
 21. Themethod according to claim 10, further comprising the step of clampingsaid connector to a coaxial cable having an annular corrugated outerconductor.
 22. A coaxial cable assembly, the assembly comprising: a RFcoaxial cable, comprising: an annular corrugated outer conductor; acenter conductor; and a dielectric material between said outer conductorand said center conductor; and a one step connector attached to one endof said RF coaxial cable, comprising: an outer conductor clampingbacknut; a body threadably attached to said backnut; a collet seated insaid body having resilient fingers which close radially; and an O-ring,wherein the O-ring initially resides in a cavity located between saidcollet and said backnut, whereby said resilient fingers push said O-ringfrom said cavity when said backnut is threadably attached to said body.23. The assembly according to claim 22, wherein said body comprises afirst end with a threaded interior portion; and said back nut comprisesa threaded exterior portion.
 24. The connector according to claim 22,wherein said body further comprises a taper between a base and a side ofsaid body, whereby said taper on said body closes said resilient fingersradially by pressing on an end of said resilient fingers.
 25. Theconnector according to claim 22, wherein said collet further comprises aramp located midway of said resilient fingers, whereby said ramp makescontact with an interior surface of said back nut and closes saidresilient fingers.
 26. The connector according to claim 22, wherein saidcollet further comprises a tab and said back nut further comprises ashoulder, whereby said shoulder provides rigidity to said collet byengaging said tab of said collet.
 27. The connector according to claim22, wherein said O-ring is lubricated and oversized, whereby said O-ringpasses freely over a cable, whereby said resilient fingers push saidO-ring from said cavity to a corrugation groove in said cable's outerconductor when said backnut is threadably attached to said body.
 28. Theconnector according to claim 22, wherein said back nut further comprisesa bore, whereby said bore compresses said O-ring when said connector isclamped to a cable.
 29. The connector according to claim 24, whereinsaid collet further comprises a ramp located about midway of saidresilient fingers and a tab; wherein said body comprises a first endwith a threaded interior portion; wherein said O-ring is oversized;wherein said resilient fingers push said O-ring from said cavity to acorrugation groove in said cable's outer conductor when said backnut isthreadably attached to said body; and wherein said back nut comprises athreaded exterior portion, an interior surface, a shoulder and a bore,whereby said ramp makes contact with an interior surface of said backnut and closes said resilient fingers, said shoulder provides rigidityto said collet by engaging said tab of said collet, and said borecompresses said O-ring when said connector is clamped to a cable.